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<HEAD>
              Factopedia                             <TITLE> Sum of first 5 natural numbers </TITLE>


                                                 </HEAD>
                                                 <BODY>
                                                 <SCRIPT>
                                                   var sum = 0;
                                                   for(var i=1; i <= 5; i++)
                                                   {

                                                     sum = sum + i;
                    Some programming
                                                   }
                       languages use
                                                   document.write("Sum of first 5 natural numbers
                   semicolon at the end
                                                 = ", sum);
                    of the statement to
                     terminate it. But in        </SCRIPT>
                    JavaScript, you can          </BODY>
                    start your statement         </HTML>
                      with semicolon.










                                                            Let’s Back-uP
                         JavaScript                 •   In JavaScript, the statements that are used to repeat a set
                    frameworks are best                 of instructions are called iterative or looping statements
                   suited for mobile app                or simply loops.
                       development.
                                                    •   The for statement or loop is used to repeat an instruction
                                                        or a set of instructions for a fixed number of times.

                                                    •   The  while  statement  or  loop  is  used  to  repeat  a  set  of
                                                        instructions until a conditional expression returns True.
                                                    •   The do-while loop is used to execute a set of statements
                                                        repeatedly, if the number of iterations is not known.
                                                    •   When a loop is used inside another loop then it is called a
                      JavaScript is not
                    allowed Hyphens in                  nested loop.
                    the varibale names.             •  The loop that is never ends is called infinite loop.
                      Hyphens will be               •   The  break  statement  halts  the  execution  of  a  loop  and
                     identified as minus                program flow switches to the statement after the loop.
                            sign.                   •   The continue statement stops the execution of the current
                                                        iteration of the loop and sends the control of the program
                                                        to the beginning of the loop for next iteration.




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